Method for the recovery of metals from electronic waste

Abstract

A method for obtaining metals of the 8th to 14th groups, in particular raw copper, comprises the following steps: i) providing and melting down a mixed feed comprising electronic waste in a smelting reactor, so that a first melt with a first metallic phase and a first slag phase is formed; ii) separating out the first slag phase from the smelting reactor; iii) refining the remaining first metallic phase by means of an oxygen-containing gas, possibly with the addition of copper-containing residual materials, so that a second, copper-enriched slag phase is formed; iv) possibly separating off the second slag phase and repeating the step; v) separating off the refined first metallic phase from the smelting reactor; and vi) adding a further mixed feed comprising electronic waste to the remaining second, copper-enriched slag phase and repeating process steps i) to vi).

The invention claimed is: 
     
         1 . A method for obtaining metals of the 8th to 14th groups, comprising the steps of:
 i) providing and melting down a mixed feed comprising electronic waste in a smelting reactor, so that a first melt with a first metallic phase and a first slag phase is formed;   ii) removing the first slag phase from the smelting reactor;   iii) refining the first metallic phase that remains in the smelting reactor by an oxygen-containing gas, thereby forming a refined first metallic phase and a second, copper-enriched slag phase;   iv) removing the refined first metallic phase from the smelting reactor; and   v) adding a further mixed feed comprising electronic waste to the second, copper-enriched slag phase that remains in the smelting reactor and repeating process steps i) to v).   
     
     
         2 . The method according to  claim 1 , wherein the first slag phase is reduced by a reducing agent. 
     
     
         3 . The method according to  claim 1 , wherein steps i) to v) are carried out at a temperature of at least 1150° C. 
     
     
         4 . The method according to  claim 1 , wherein the mixed feed comprises the electronic waste in an amount of at least 10 wt %. 
     
     
         5 . The method according to  claim 1 ,
 wherein the mixed feed comprises a slag-forming agent and/or   wherein a slag-forming agent is added to the process in steps i) and/or iii).   
     
     
         6 . The method according to  claim 5 , wherein the mixed feed comprises the slag-forming agent in an amount of at least ⅛ of the mass fraction of the electronic waste present in the mixed feed. 
     
     
         7 . The method according to  claim 5 , wherein the slag-forming agent is selected from the group consisting of iron, iron oxides, calcium oxide, calcium carbonate, calcium hydroxide, magnesium oxide, magnesium carbonate, magnesium hydroxide, sodium oxide, sodium carbonate, sodium hydroxide, silicon dioxide, silicon carbonate, and silicon hydroxide. 
     
     
         8 . The method according to  claim 1 , wherein the electronic waste comprises an aluminum content of 0.1 to 20.0 wt %. 
     
     
         9 . The method according to  claim 1 , wherein the electronic waste comprises an organic content of 5.0 to 80.0 wt %. 
     
     
         10 . The method according to  claim 1 , wherein the electronic waste is crushed to a particle size smaller than 20 inches, and optionally provided in the form of pressed articles in accordance with step i). 
     
     
         11 . The method according  claim 1 , wherein step i) is assisted by selectively injecting an oxygen-containing gas. 
     
     
         12 . The method according to  claim 1 , wherein the metallic phase is removed via a tapping opening arranged in a bottom and/or in a side wall of the smelting reactor. 
     
     
         13 . The method according to  claim 1 , further comprising:
 introducing copper-containing residual materials into the smelting reactor while refining the first metallic phase, whereby a further slag phase is formed; and   removing the further slag phase from the smelting reactor before removing the refined first metallic phase.   
     
     
         14 . The method according to  claim 1 , wherein the copper-enriched slag phase remaining in the smelting reactor comprises copper oxide (Cu 2 O). 
     
     
         15 . The method according to  claim 14 , further comprising transferring the copper oxide (Cu 2 O) remaining in the smelting reactor into the first metallic phase during a subsequent step i) as a result of prevailing reducing conditions in the smelting reactor. 
     
     
         16 . A method for obtaining raw copper, comprising:
 i) providing and melting down a mixed feed comprising electronic waste in a smelting reactor, so that a first melt with a first metallic phase and a first slag phase is formed;   ii) removing the first slag phase from the smelting reactor;   iii) refining a remaining first metallic phase by an oxygen-containing gas, thereby forming a refined first metallic phase and a second, copper-enriched slag phase;   iv) removing the refined first metallic phase from the smelting reactor; and   v) introducing a further mixed feed comprising electronic waste to the second slag phase that remains in the smelting reactor and repeating process steps i) to v).